Governor for fire-engines.



Mr/vfss 5 w- .4 49.

F. HOFFMAN.

GOVERNOR FOR FIRE ENGINES.

APPLICATION FILED oo'r; 25, 1913.

L@93,585D Patented Apr. 14, 1914..

less pressure upon valve 21,. so that after adjusted to a certain pressure, said valve will open only when water forced into pipesection 17, by the pump, has attained a cor responding pressure which is sufiicient to overcome the resistance of the spring. This latter is adjusted for this purpose by means of a screw-threaded stem 26, manipulated by a hingedly connected handle 27 and seated in a threaded neck 28. Stem 26 acts upon the spring by means of an interposed disk 29. A dialplate 31 is provided in conjunction with handle 27 and has spaced notches in its edge, as shown in Fig. 3, adapted to receive the free end of the handle. For manipulation, the handle is lifted and after turned to a certain notch to adjust the sp'ri ng to the pressure indicated by the number opposite such notch, it is dropped into the same to be held. thereby.

If the pressure is to be changed the handle is moved to a different notch which corresponds to this different pressure.

Between piston 15 and a disk 32, against which spring 13 bears, there is a stem F which, as far as its function and o eration is concerned, may be considered as eing of one piece and continuous although, to facilita'te its manufacture and assembling, it-may be made up of two or more sections. Near its ends it is supported and ided' in structural parts 33 and 34, whicli close housing 14 and cylinder 16 respectively, against valve housing e. Valve E is provided with a sleeve 35, which extends laterally from one side thereof and by means of which it is mounted upon the middle-portion 36, of stem F. On its other side, valve E is provided. with a valve seat, and an auxiliary valve 37 connected to stem-portion 36 is fitted thereto. On the other end of sleeve 35, a follower 38 is provided and fitted into .a lateralv extension 39, ofvalve-housing e, which extension forms a chamber 40. Beyond the follower a shoulder 41 is provided on stem F, which may be formed by a collar or pin, whereby the action of spring 13 is transmitted to valve F to hold this latter normally open, as before described. Valve E is mounted upon stem-portion 36 in a manner to have a limited axial movement between this shoulder 41 and auxiliary valve 37, the two being spaced accordingly. The formation of the outside ofstem-portion 36 and of the opposite surface in the hollow part of sleeve 35 is such as to provide clearance as shown in the drawing and permits communication between valve-housing c, and chamber 40, except as far as it is controlled by auxiliary valve 37. fore stated, valve E is nor really open, held so byspring 13, and does not interfere with the free admission of steam to the engine and the control of thesame by throttle-valve 9. Steam, as soon as admitted, lies therefore against both sides of valve E, so that the same occupies a balanced position. If the water pumped exceeds the intended pressure, the resistance of spring 23, adjusted accordingly by handle 27, is overcome, valve 21 will be raised and water will force its way ast it and through pipe conduit a, into cy lnder 16. Observe dotted line between arrows in Fig. 2. There, the water acts against piston 15 and stem F, moving first the auxiliary valve against valve-E which contact finally causes this latter valve to move toward its seat. The clear passage space between valve E and its seat is thereby reduced and the steam suppl to the engine is cut down accordingly. l hus the opposing actions of spring 13 against one end of stem F, and of the water-pressure against the plston at the other end of they stem, tend to hold valve E, in a variable, but balanced and open position so that a waterpressure is maintalned which is constant and normal with respect to the pressure it is intended to carry at the time and as de- .termined and controlled by valve 21.

Should valve E, close entirely, the operative speed of engine and pump will decline rapidly, causing the water-pressure to drop correspondingly. The action of the factors which balance stem F, being thus disturbed, spring 13 will presently overcome the reduced water-pressure and shift said stem, causing thereby movement of auxiliary valve 37 independent of valve E. Steam is thereby permitted to enter between stem-portion 36, and sleeve 35, into chamber 40, where, by acting against follower 38, valve E becomes again balanced so as to permit spring 13 to move it readily into open position, thus restoring free passage of steam. To render these fluctuations possible, provision must of course be made for escape of the water confined. between valve 21 and piston 15 in pipe sections 18 and 19, to permit piston 15, to yield to the action of spring 13. For such purpose a waste-pipe 42 is provided through which the water may escape. Thls pipe is constantly open and a valve, contained in housing 43 is provided to adjust this wastage, to maintain it within proper limits so as not to impair the intended action with respect to piston-l5, of the water admitted by valve 21 into pipe sections 18 and 19. A handle 44, in connection with a notched dialplate 45, and attached to stem 46, of this valve, is provided for the purpose of facilitating this adjustment.

A gage 47 permits observation of pressure conditions in the part of pipe conduit a, between valve 21 and piston 15. It may be mentioned here, that this pressure is less tionately the same as if this action were obtained by the pressure of the pumped water directly.

48 and 49 are waste-pipes to drain cylinder 16 and housing 14 respectively.

The device is constructed in a manner to permit its convenient connection to existing engines, clamping brackets 03 fitted for attachment to frame D, as shown in Fig. 5, being provided for the purpose.

The use of the device may be dispensed with, if necessary for any purpose and without interfering with the operation of theengine, by. cutting off the flow of water through it, 'a valve- 51 being provided for this purpose in-pipe section 17. In that case the usual pressure-gage 52, present in engines, to show the Water pressure, is used to observe and manage the operation of the pump. A strainer 53 is provided in pipesection 17 to prevent matter like sand from entering the device.

54 is an adjusting screw serving to maintain spring 13, in proper pressure condition.

Having described my mvention, I claim as new:

1. In means for controlling the pressure of Water pumped by a steam-operated pump, the combination of a valve-housing, a spring-housing provided on one side thereof and a cylinder which forms a water-chamber provided in axial alinement therewith on its other side, and both closed against the valve-housing, a stem which traverses the valve housing and extends therefrom respectively into the spring-housing and into the water-chamber mentioned, a valve supported on the stem-portion which traverses the valve-housing, a spring contained in the spring-housing and adapted to act against that portion of the stem which extends into it, a piston in the water-chamber adapted to act against that portion of the stem which extends into it and means to admit water from the pump into the water-chamber.

2. In means for controlling water-pressure, the combination of a pump, a steamengine to operate it, a steam-pipe to supply this latter, a throttle-valve in this steampipe to control the passage of steam therethrough, an automatic valve adapted to control the passage of steam between the throttle-valve and the steam engine, an auxiliary valve seated upon the. automatic valve, a stem on which both valves are supported in a manner that one may move independently of the other the auxiliary valve being rigidly connected, 9. spring adapted to act against one end of this stem, a piston at the other end of it and means toadmit pumped waterto the piston so as to cause it to act upon the stem in opposition to the spring mentioned and to move the auxiliary valve against the automatic valve.

3. In means for controlling water pressure, the combination of a pump, a steamengine to operate it, a steam-pipe to supply this latter, a throttle-valve in this steampipe to control the passage of steam therethrough, a valve-housing between the throttle-valve and the steam-engine, an extension on one side of this housing forming a steamchamber, a cylinder forming a Water-chamber on the other side of this housing and a spring-housing beyond the steam-chamber all three being axially alined, a valve contained in the valve-housing and adapted to control passage of steam through the steam pipe, a follower fitted to the steam-chamber and forming a connected part of the valve, an auxiliary valve adapted to admit steam to'the steam-chamber so as to act against the follower contained therein; a stem whereby the valves mentioned are supported in a manner that one may move independently of the other and which stem extends from the spring-housing, throughthe steam-chamber and valve-housing and into the waterchamber, a spring contained inr the springhousing and acting against the stem in a manner that passage for steam through the valve-housing is normally open, a pistonv contained in the water-chamber and'means to admit pumped water to this chamber so as to cause the piston contained therein to act against the stem in opposition to the spring mentioned. j

4. In means for controlling the pressure of the water moved by the pump of a steamoperated fire-engine, the combination of the pump, steam-engine and boiler, a frame whereby these parts are supported, a steampipe to supply the engine from the boiler, a throttle-valve provided in this steam-pipe to control the steam-supply to the engine, a

spring-actuated valve which controls passage through the steam-pipe between the throttle-valveand the engine and tends to keep this passage normally open, a housing in which this valve is contained and which forms a part of the steam-conduit between the boiler and the engine, an operatively connected piston adapted to operate in amanner tending to close this valve, a cylinder which forms a connected extension of the housing mentioned and constitutes a Waterchamber closed against said housing and to which the piston is fitted, a pipe-conduit whereby this water-chamber is connected with the pump-delivery, means to connect this pipe-conduit in position to' the longitudinal members of the frame mentioned, av duit between this housing and the waterspring-actuated valve which controls passage of water to the water-chamber and makes such passage dependent on pressureconditions of the pumped water, adjusting means to regulate the action of this valve, a housing in which it is contained and a normally open waste-outlet in the pipe eonchamber. 10 In testimony whereof, I hereunto afiix my signature in the presence of two witnesses. FRANK HOFFMAN. Witnesses:

C. SPENGEL,

. A. JOHNSON. 

